package thread2;
import java.io.*;
import java.nio.*;
import java.nio.channels.*;
import java.nio.charset.*;
import java.net.*;
import java.util.*;
public class EchoServer{
private Selector selector = null;
private ServerSocketChannel serverSocketChannel = null;
private int port = 8000;
private Charset charset=Charset.forName("GBK");
public EchoServer()throws IOException{
selector = Selector.open();
serverSocketChannel= ServerSocketChannel.open();
serverSocketChannel.socket().setReuseAddress(true);
serverSocketChannel.socket().bind(new InetSocketAddress(port));
System.out.println("服务器启动");
}
public void accept(){
for(;;){
try{
SocketChannel socketChannel = serverSocketChannel.accept();
System.out.println("接收到客户连接，来自:" +
socketChannel.socket().getInetAddress() +
":" + socketChannel.socket().getPort());
socketChannel.configureBlocking(false);
ByteBuffer buffer = ByteBuffer.allocate(1024);
synchronized(gate){
selector.wakeup();
socketChannel.register(selector,
SelectionKey.OP_READ |
SelectionKey.OP_WRITE, buffer);
}
}catch(IOException e){e.printStackTrace();}
}
}
private Object gate=new Object();
public void service() throws IOException{
for(;;){
synchronized(gate){}
int n = selector.select();
if(n==0)continue;
Set readyKeys = selector.selectedKeys();
Iterator it = readyKeys.iterator();
while (it.hasNext()){
SelectionKey key=null;
try{
key = (SelectionKey) it.next();
it.remove();
if (key.isReadable()) {
receive(key);
}
if (key.isWritable()) {
send(key);
}
}catch(IOException e){
e.printStackTrace();
try{
if(key!=null){
key.cancel();
key.channel().close();
}
}catch(Exception ex){e.printStackTrace();}
}
}//#while
}//#while
}
public void send(SelectionKey key)throws IOException{
ByteBuffer buffer=(ByteBuffer)key.attachment();
SocketChannel socketChannel=(SocketChannel)key.channel();
buffer.flip(); //把极限设为位置
String data=decode(buffer);
if(data.indexOf("\n")==-1)return;
String outputData=data.substring(0,data.indexOf("\n")+1);
System.out.print(outputData);
ByteBuffer outputBuffer=encode("echo:"+outputData);
while(outputBuffer.hasRemaining())
socketChannel.write(outputBuffer);
ByteBuffer temp=encode(outputData);
buffer.position(temp.limit());
buffer.compact();
if(outputData.equals("bye\r\n")){
key.cancel();
socketChannel.close();
System.out.println("关闭与客户的连接");
}
}
public void receive(SelectionKey key)throws IOException{
ByteBuffer buffer=(ByteBuffer)key.attachment();
SocketChannel socketChannel=(SocketChannel)key.channel();
ByteBuffer readBuff= ByteBuffer.allocate(32);
socketChannel.read(readBuff);
readBuff.flip();
buffer.limit(buffer.capacity());
buffer.put(readBuff);
}
public String decode(ByteBuffer buffer){ //解码
CharBuffer charBuffer= charset.decode(buffer);
return charBuffer.toString();
}
public ByteBuffer encode(String str){ //编码
return charset.encode(str);
}
public static void main(String args[])throws Exception{
final EchoServer server = new EchoServer();
Thread accept=new Thread(){
public void run(){
server.accept();
}
};
accept.start();
server.service();
}
}
/****************************************************
* 作者：孙卫琴 *
* 来源：<<Java网络编程精解>> *
* 技术支持网址：www.javathinker.org *
***************************************************/